In a nutshell the world could be a more peaceful and productive place. However it would be increasingly westernized and much of its splendiferous beauty would be lost. People would begin to slowly stop speaking their mother tongue languages.
In conclusion, I think that every country of the world should introduce English into their school curriculum. It may open the door to new opportunities, help people break the poverty cycle and avoid misunderstandings. However the importance of one's cultural identity should always be emphasized.
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